First-principle calculation of core level binding energies of LixPOyNz solid electrolyte.

We present first-principle calculations of core-level binding energies for the study of insulating, bulk phase, compounds, based on the Slater-Janak transition state model. Those calculations were performed in order to find a reliable model of the amorphous Li_xPO_yN_z solid electrolyte which is able to reproduce its electronic properties gathered from X-ray photoemission spectroscopy (XPS) experiments. As a starting point, Li₂PO₂N models were investigated. These models, proposed by Du et al. on the basis of thermodynamics and vibrational properties, were the first structural models of Li_xPO_yN_z. Thanks to chemical and structural modifications applied to Li₂PO₂N structures, which allow to demonstrate the relevance of our computational approach, we raise an issue concerning the possibility of encountering a non-bridging kind of nitrogen atoms (=N^-) in Li_xPO_yN_z compounds. [ABSTRACT FROM AUTHOR]